Optical filters provide various important applications in optical fiber systems. Typically, they are used, for example, as bandpass filters, as noise blocking filters and as pump blocking filters. When used as bandpass filters, they provide for channel selection in wavelength-division multiplexing. When used as noise and pump blocking filters they are used with optical amplifiers. Presently, bulk filters when used for fiber-to-fiber coupling require expanded beam optics. Normally, these filters are expensive to produce and require lens alignment elements which are relatively large, unstable and complicated. Clearly, a need exists for an inexpensive filter which is not only compatible with optical fibers but does not require the relatively large cumbersome structure now required.